Question

我在项目中一起实现了Drag-Sort ListView（DSLV）和LazyList，我从github下载了演示LazyList和Drag-Sort ListView，然后根据我的要求进行集成和修改，

我使用DSLV进行拖动并对ListView和LazyList的项进行排序，以便从URL显示图像，我只是从DSLV实施“基本使用操场”进行拖动和排序，

我在TestBedDSLV.java中实现了搜索，但问题是当我从列表中搜索内容，但我无法更新列表时，我已经尝试过notifyDataSetChanged方法但它不起作用，通常我们创建新的适配器并将其传递给listview，如lv.setAdapter（adapter），但这里只是设置ListAdapter，所以我们不能做lv.setAdapter（适配器）

TestBedDSLV.java

package com.mobeta.android.demodslv;

import android.os.Bundle;
import android.support.v4.app.Fragment;
import android.support.v4.app.FragmentActivity;
import android.text.Editable;
import android.text.TextWatcher;
import android.view.Menu;
import android.view.MenuInflater;
import android.widget.Button;
import android.widget.EditText;

import com.mobeta.android.dslv.DragSortController;
import com.mobeta.android.dslv.DragSortListView;

public class TestBedDSLV extends FragmentActivity { 

private int mNumHeaders = 0;
private int mNumFooters = 0;

private int mDragStartMode = DragSortController.ON_DOWN;
private boolean mRemoveEnabled = false;
private int mRemoveMode = DragSortController.FLING_RIGHT_REMOVE;
private boolean mSortEnabled = true;
private boolean mDragEnabled = true;

private String mTag = "dslvTag";
Button search;
EditText search_customer;

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.test_bed_main);

    search = (Button) findViewById(R.id.btn_search);
    search_customer = (EditText) findViewById(R.id.search_product);

    search_customer.addTextChangedListener(new TextWatcher() {

        @Override
        public void onTextChanged(CharSequence s, int start, int before,
                int count) {

            // here is logic for refresh the list View
        }

        @Override
        public void beforeTextChanged(CharSequence s, int start, int count,
                int after) {

        }

        @Override
        public void afterTextChanged(Editable s) {

        }
    });

    if (savedInstanceState == null) {
        getSupportFragmentManager().beginTransaction()
                .add(R.id.test_bed, getNewDslvFragment(), mTag).commit();
    }
}

@Override
public boolean onCreateOptionsMenu(Menu menu) {
    MenuInflater inflater = getMenuInflater();
    inflater.inflate(R.menu.mode_menu, menu);
    return true;
}


private Fragment getNewDslvFragment() {
    DSLVFragmentClicks f = DSLVFragmentClicks.newInstance(mNumHeaders,
            mNumFooters);
    f.removeMode = mRemoveMode;
    f.removeEnabled = mRemoveEnabled;
    f.dragStartMode = mDragStartMode;
    f.sortEnabled = mSortEnabled;
    f.dragEnabled = mDragEnabled;
    return f;
}
}

DSLVFragmentClicks.java

package com.mobeta.android.demodslv;

import android.view.View;
import android.widget.AdapterView;
import android.widget.ListView;
import android.os.Bundle;
import android.widget.Toast;

public class DSLVFragmentClicks extends DSLVFragment {

public static DSLVFragmentClicks newInstance(int headers, int footers) {
    DSLVFragmentClicks f = new DSLVFragmentClicks();

    Bundle args = new Bundle();
    args.putInt("headers", headers);
    args.putInt("footers", footers);
    f.setArguments(args);

    return f;
}

AdapterView.OnItemLongClickListener mLongClickListener = 
        new AdapterView.OnItemLongClickListener() {
            @Override
            public boolean onItemLongClick(AdapterView<?> arg0, View arg1, int arg2,
                    long arg3) {
                String message = String.format("Long-clicked item %d", arg2);
                Toast.makeText(getActivity(), message, Toast.LENGTH_SHORT).show();
                return true;
            }
        };

@Override
public void onActivityCreated(Bundle savedState) {
    super.onActivityCreated(savedState);

    ListView lv = getListView();
    lv.setOnItemClickListener(new AdapterView.OnItemClickListener() {
        @Override
        public void onItemClick(AdapterView<?> arg0, View arg1, int arg2,
                long arg3) {
            String message = String.format("Clicked item %d", arg2);
            Toast.makeText(getActivity(), message, Toast.LENGTH_SHORT).show();

        }
    });
    lv.setOnItemLongClickListener(new AdapterView.OnItemLongClickListener() {
        @Override
        public boolean onItemLongClick(AdapterView<?> arg0, View arg1, int arg2,
                long arg3) {
            String message = String.format("Long-clicked item %d", arg2);
            Toast.makeText(getActivity(), message, Toast.LENGTH_SHORT).show();
            return true;
        }
    });
}
}

DSLVFragment.java

package com.mobeta.android.demodslv;

import java.util.ArrayList;
import java.util.Arrays;

import android.os.Bundle;
import android.support.v4.app.ListFragment;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.ArrayAdapter;

import com.mobeta.android.dslv.DragSortController;
import com.mobeta.android.dslv.DragSortListView;

public class DSLVFragment extends ListFragment {

ArrayAdapter<String> adapter;

private String[] array;
public static ArrayList<String> list;

private DragSortListView.DropListener onDrop = new DragSortListView.DropListener() {
    @Override
    public void drop(int from, int to) {
        if (from != to) {
            String item = adapter.getItem(from);
            adapter.remove(item);
            adapter.insert(item, to);
        }
    }
};

private DragSortListView.RemoveListener onRemove = new DragSortListView.RemoveListener() {
    @Override
    public void remove(int which) {
        adapter.remove(adapter.getItem(which));
    }
};

protected int getLayout() {
    return R.layout.dslv_fragment_main;
}

/**
 * Return list item layout resource passed to the ArrayAdapter.
 */
protected int getItemLayout() {
    return R.layout.list_item_handle_right;

}

private DragSortListView mDslv;
private DragSortController mController;

public int dragStartMode = DragSortController.ON_DOWN;
public boolean removeEnabled = false;
public int removeMode = DragSortController.FLING_RIGHT_REMOVE;
public boolean sortEnabled = true;
public boolean dragEnabled = true;

public static DSLVFragment newInstance(int headers, int footers) {
    DSLVFragment f = new DSLVFragment();

    Bundle args = new Bundle();
    args.putInt("headers", headers);
    args.putInt("footers", footers);
    f.setArguments(args);

    return f;
}

public DragSortController getController() {
    return mController;
}

/**
 * Called from DSLVFragment.onActivityCreated(). Override to set a different
 * adapter.
 */
public void setListAdapter() {
    array = getResources().getStringArray(R.array.jazz_artist_names);
    list = new ArrayList<String>(Arrays.asList(array));

    adapter = new ArrayAdapter<String>(getActivity(), getItemLayout(),
            R.id.text, list);
    setListAdapter(adapter);
}

/**
 * Called in onCreateView. Override this to provide a custom
 * DragSortController.
 */
public DragSortController buildController(DragSortListView dslv) {
    DragSortController controller = new DragSortController(dslv);
    controller.setDragHandleId(R.id.drag_handle);
    controller.setClickRemoveId(R.id.click_remove);
    controller.setRemoveEnabled(removeEnabled);
    controller.setSortEnabled(sortEnabled);
    controller.setDragInitMode(dragStartMode);
    controller.setRemoveMode(removeMode);
    return controller;
}

/** Called when the activity is first created. */
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
        Bundle savedInstanceState) {
    mDslv = (DragSortListView) inflater.inflate(getLayout(), container,
            false);

    mController = buildController(mDslv);
    mDslv.setFloatViewManager(mController);
    mDslv.setOnTouchListener(mController);
    mDslv.setDragEnabled(dragEnabled);

    return mDslv;
}

@Override
public void onActivityCreated(Bundle savedInstanceState) {
    super.onActivityCreated(savedInstanceState);

    mDslv = (DragSortListView) getListView();

    mDslv.setDropListener(onDrop);
    mDslv.setRemoveListener(onRemove);

    Bundle args = getArguments();
    int headers = 0;
    int footers = 0;
    if (args != null) {
        headers = args.getInt("headers", 0);
        footers = args.getInt("footers", 0);
    }
    setListAdapter();
}
}

test_bed_main.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:orientation="vertical" >

<LinearLayout
    android:id="@+id/search_lay"
    android:layout_width="fill_parent"
    android:layout_height="wrap_content"
    android:focusable="true"
    android:focusableInTouchMode="true"
    android:orientation="horizontal" >

    <EditText
        android:id="@+id/search_product"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:layout_marginBottom="2dp"
        android:layout_marginLeft="5dp"
        android:layout_marginTop="2dp"
        android:layout_weight="1"
        android:background="@drawable/search_back"
        android:hint="Enter Firstname"
        android:imeOptions="actionSearch"
        android:inputType="text"
        android:paddingBottom="2dp"
        android:paddingLeft="5dp"
        android:paddingTop="2dp"
        android:visibility="visible" />

    <Button
        android:id="@+id/btn_search"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:layout_marginLeft="5dp"
        android:layout_marginRight="5dp"
        android:layout_weight="2.5"
        android:text="CANCEL"
        android:textColor="#155280"
        android:textSize="14sp"
        android:textStyle="bold"
        android:visibility="visible" />
</LinearLayout>

<FrameLayout
    android:id="@+id/test_bed"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent" />
<!-- We will add the DSLVFragment inside the FrameLayout in code -->

</LinearLayout>

enter image description here

和其他需求类可以从我上面给出的github链接下载.....

Answer 1

实际上，如果你看到你的代码是关闭的，那就是你提到的方法

public void setListAdapter() {
    array = getResources().getStringArray(R.array.jazz_artist_names);
    list = new ArrayList<String>(Arrays.asList(array));

    adapter = new ArrayAdapter<String>(getActivity(), getItemLayout(),
            R.id.text, list);
    setListAdapter(adapter);
}

所以你说： “通常我们创建新的适配器并将其传递给listview，如lv.setAdapter（adapter），但在这里他们只设置ListAdapter，所以我们不能做lv.setAdapter（适配器）”

通过根据搜索轻松生成数组并将其设置为代码??

，您是否可以轻松完成此操作

list = new ArrayList<String>(Arrays.asList(array));

        adapter = new ArrayAdapter<String>(getActivity(), getItemLayout(),
                R.id.text, list);
        setListAdapter(adapter);

编辑：我认为你问的是错误的问题。您的主要关注点应该是如何在活动和片段之间进行通信......因为您的搜索功能处于活动状态且列表处于片段状态。因此，您需要设置一个基本上将搜索字符串传递给您的片段的接口，然后您可以创建一个数组并按照您现在所做的相同方式设置它。

阅读this如此问答。在答案中，您将找到一种类似的方法来在活动和片段之间传递数据。

编辑2：你主要关心的是从活动到片段的沟通..声明你的活动中的界面是这样的：

    public interface FragmentCommunicator{
       public void passDataToFragment(String someValue);
    }

then call the interface at your text change listener..for example

    FragmentCommunicator mfragmentCommunicator;
    //your onCreate function 
    {
    //your textchangelistenr
    {
    onTextChanged call 
if(mfragmentCommunicator != null)
   mfragmentCommunicator.passDataToFragment(Pass your string here)
    }

then make your fragement implement this interface like

public class someFragment extends Fragment implements FragmentCommunicator
{
//this is your rest of the fragment

@Override
public void passDataToFragment(String somevalue)
{
//This function will get fired each time your text is changed since in your activity you are calling this same function in your textchange listener. the String somevalue will be the string that you passed from your activity


}

//rest of the code
.
.
.
//Don't forget to initialize your interface in fragment itself. Do this in your onAttach
like this
@Override
 public void onAttach(Activity activity){
  super.onAttach(activity);
  context = getActivity();

  ((MainActivity)context).fragmentCommunicator = this;
}

}

}

您可以参考this链接获取进一步说明。仅检查FragmentCommunicator的实现

Answer 2

如果您使用数组作为适配器的基本arraylist，只需更新此数组并调用adapater.notifyDataSetChanged（）。这将更新DSLV，因为我在我的一个项目中使用了相同的方法。

如何在Drag-Sort ListView中刷新ListView？

2 个答案: